Some HVAC units use actuators for doors. These doors, when closing, may cause a substantial about of noise or audible sounds that may be undesirable for the consumer in an air conditioned automotive unit. For example, current cable operated HVAC door technology does not incorporate a mechanism to reduce door acceleration to prevent door audible noise when the door contacts a sealing surface. Most HVAC unit designs today utilize electric actuated kinematics where door speed is managed at a constant speed with the actuator in order to mitigate door noise.
One solution to the foregoing noise problem includes overmolding foam on the door as a dampener to mitigate door slap noise. In fact, a number of HVAC door designs today are using over molded santoprene architecture. This design is more conducive because there is plastic to plastic contact (door and sealing surface). However, there is still a need to find a mechanism to mitigate or reduce the noise to less audible levels to comply with consumer desires.
In the prior art, for example, some doors turn or rotate around an axis, and need to be stopped at a certain point. These doors often include pieces provided with surfaces at end points thereof that are modified in order to stop further movement of the door. These piece also prevent the door from turning too far and hitting or slapping a wall or other feature. When the door hits or slaps the wall or other feature, it is accompanied with the element of noise.
Other features have been described that immobilize a body that turns or rotates around an axis, such as in FR 2 803 054 A1. These features stop the movement of the body before the body gets to an angular immobilization position. By putting a tab or finger on the rotating body itself, the tab or finger can be displaced in such a way that the finger does not contact a cam or other feature, or slow down the door's movement until the door reaches an extreme end of its trajectory.
Other solutions to the noise problem have been attempted to mitigate or reduce the noise of HVAC units, however, a constant deceleration method of the type disclosed herein below has not been described in the prior art.